After landing Jarome Iginla, Brenden Morrow, Jussi Jokinen and Douglas Murray without giving up a significant roster player, Ray Shero and the Pittsburgh Penguins were considered the runaway NHL trade deadline winners.

However, their underlying numbers since the deadline (despite a percentages-buoyed record) tell another story. In fact, the Penguins sported the second-worst possession rate of any club in the league since April 3 (43.08 percent Corsi), ahead of only the Toronto Maple Leafs (41.92 percent).

Remember: 5-on-5 Corsi Percentage is the ratio of a team’s shot attempts (goals, saved shots, blocked shots, and missed shots) in comparison to its opponents during 5-on-5 play. The higher the rating, the better.

No doubt a big part of the Penguins' significant dip were dual injuries to Sidney Crosby (who missed all 11 games with a broken jaw) and Evgeni Malkin (who missed four). Crosby is the best center in the game and the lynchpin in the Penguins' game plan: he faces the other team’s top players and drives possession better than any other guy on the club.

Malkin has a similar effect, if in somewhat easier circumstances (lesser competition and a lot more offensive zone draws). Their influence can be seen in WOWY (with or without you) reports via Hockey Analysis. Pittsburgh’s Corsi rate with Sidney this year was about 56 percent. Without him? About 46 percent.

That’s huge, but it doesn’t quite explain the degree to which Pittsburgh’s possession rate cratered without him. After all, this is a club that excelled without their captain for large swaths of time in both 2010-11 and 2011-12. As a result, the overarching assumption about the Pens is that they are a fundamentally sound club even without their superstars and that additions like Iginla, Morrow and Murray were only further buttresses to an already capable supporting cast.

But instead, the Pens put up near league-worst shot differential rates in the absence of their big guns. That, in no small part, is because of lot of their additions have been possession black holes since landing in Pittsburgh.

Check out the Corsi-close rates (Corsi while a game is within one goal either way) of the new additions:

Iginla: 55.5 percent

Jokinen: 45.4 percent

Murray: 40.7 percent

Morrow: 36.3 percent

Iginla’s the only one above board and given he’s been mediocre or worse at driving the play north for years, we can safely guess his numbers are in part due to circumstances, rather than ability. Morrow and Murray’s rates are quite awful, which in Murray’s case is no surprise.

There are probably a few more reasons for the Penguins' outshooting collapse post-deadline: concurrent injuries to James Neal and Kris Letang that further eroded the Pens depth, as well the absence of Jordan Staal, since his replacement, Brandon Sutter, is nowhere near as capable at driving possession from the third line (Sutter’s Corsi rate this season is an abysmal minus-16.62/60, or about 42.6 percent). Staal was one of the club’s pillars that held things up whenever they lost Malkin and/or Crosby previously. With him now in Carolina and young Sutter failing to fill his shoes, Pittsburgh’s bottom six is worse off.

Overall, none of this will matter too much if Pittsburgh can stay healthy in the playoffs. With Crosby and Malkin anchoring things up front, the Pens are in fine shape.

It’s probable, though, that they are far more vulnerable than previously thought, and that their moves at the deadline did very little to assuage that risk (perhaps even exacerbating the issue in places). As a result, the Pens' charge for another Cup could peter out if their two superstars can’t stay out of the infirmary.